1. Field of the Invention
This invention relates to a method of producing narrow tapes for use as slide fasteners, ribbons, or packing tapes, and more particularly to a method of continuously producing a narrow tape having different colors or figures by using a weft and warp yarns, the latter of which are colored automatically while they are being supplied to a weaving or knitting machine.
2. Description of the Related Art
Heretofore there are several methods of producing a narrow tape having different colors. In one of the simplest methods, while it is being moved, a monochromatic or non-colored woven tape is colored with a dye or is applied a pattern to a desired length, then being dyed with a different color or being applied a different pattern. This method is however performed only by printing. In this case, it is very difficult to have the dyes adhered on the tape uniformly and sufficiently.
To overcome this difficulty, an attempt has been made to produce such a narrow tape by using as warp yarns a variety of colored yarns which are tied, wound on bobbins, and unwound.
In a still further attempt, warp yarns are colored while they are moved to a weaving or knitting machine. For example, although it is not related to a narrow tape, Japanese Patent Laid-Open Publication No. 21488/1977 exemplifies a method of producing a tufted rug. In this method, the tufted rug is produced by weaving tufted yarns which are dyed while they are being moved to a weaving machine. According to this method, yarns for forming figures can be colored as desired simply by replacing a dye in use with another dye, which will promote production efficiency of the rugs.
In the method producing the narrow tape by a number of tied colored yarns, the yarn tying work is inevitable, which would decrease the production efficiency of the tape. This method cannot satisfy demands for production of a good assortment of tapes in a small amount.
On the other hand, if narrow tapes are made by the method of producing the tufted rug, it is impossible to change the dye instantly. In addition, a boundary between a preceding colored region and a succeeding region to be colored would be not colored properly due to running of the dye. Such boundary has to be removed from the tape in a later stage. When it is necessary to produce a narrow tape continuously by changing colors of figures or base colors, or by changing both of the colors of the figures and base colors, a great number of boundaries would be produced accordingly. For example, these boundaries each having a length corresponding to the length of two slide fastener tapes should be removed, which would reduce the production efficiency of the slide fastener tape. Specifically, when producing a variety of tapes in a small amount, it is necessary to change colors frequently, which would adversely affect the production efficiency.